bMCA Ethernet Multi-Channel Analyzer

Background

This is the Ethernet version of the bMCA-USB. Using an Ethernet connection instead of USB allows installing the device in remote places. Data transfer rates are also tremendously improved.

bMCA is a compact, digital Multi-Channel Analyzer (MCA), which is able to perform Pulse Height Analysis (PHA) of the signal produced by a standard 14-pin standard photomultiplier coupled to a scintillation detector such as NaI(Tl), LaBr3(Ce), LaCl3(Ce), CeBr3, etc.

The device is therefore useful for obtaining the energy spectrum from the photon radiation detected by the scintillator, and can be connected into the local network via a standard Ethernet connection. The device is powered via Ethernet using Power-over-Ethernet (PoE) technology.

The bMCA is provided with a basic software package that allows one to control the device, and to acquire and visualize the energy spectrum. The software incorporates an advanced and easy to use “discovery” function that can be used to detect automatically all the bMCAs (USB or Ethernet) in the neighborhood of the PC that are available for connection. A set of programming libraries are also offered, which makes the incorporation of the bMCA into existing radiation system or setup very easy. The programming libraries are available for both MS Windows and Linux operating systems.

Extremely fast data communication rates with 1K PHA spectrum being sent to the PC in 30 microseconds

Miniature design combining low-power consumption with low noise

Basic spectrum acquisition and device control software included

Available programming libraries for Windows and Linux Operating System (upon request).

LED indicators for communication status and device power, HV power and incoming count rate (ICR)

Description

The bMCA is an advanced, fully digital, compact MultiChannel Analyzer (MCA). This device is used to process the electronic pulses produced by a photomultiplier that is coupled to a scintillator detector. Such detectors are commonly used in the detection of gamma-ray radiation due to their high detection efficiency, medium energy resolution and relatively low price. This kind of MCA is able to produce an energy spectrum from the radiation events detected by the scintillator, storing it in the device’s memory for further retrieval and analysis by the PC.

The bMCA implements two modes of data acquisition:

Pulse Height Analysis (PHA)

Multi-Channel Scaling (MCS)

PHA mode is regularly used in nuclear spectrometry and radiometry, while MCS is a very useful feature for following photon detections in specific energy regions as a function of time. MCS acquisition mode is useful in both laboratory and industrial applications that make use of radioactive sources or when seeking for radioactive materials.

The bMCA design makes use of the latest advances in digital electronics. The MCA utilizes powerful digital processing techniques and algorithms to better separate the useful signal from noise and to maximize performance under high count rate conditions. The acquired spectra under PHA mode is extended for Dead Time. The device has a spectral memory size of up to 4096 channels and can perform MCS in addition to PHA.

The MCA contains a miniaturized high-voltage power supply optimized for low consumption that provides the necessary power for the PMT tube, including those used with large scintillator detectors.

The bMCA has a spectral memory size of up to 4096 channels and can perform MCS in addition to PHA. On the data communications side, this device features lighting-fast transfer rates, with a 1024-channel spectrum being trans-mitted typically in less than 30 microseconds.

A basic acquisition software package is provided for managing such device operations as setup, control, data acquisition and visualization. A digital oscilloscope function allows monitoring the input and filtered pulses to aid in fine tuning the MCA parameters. The program also includes a few spectrometry related functions for processing the spectral data: calibration, ROI analysis and peak search, to mention a few.

Technical Specifications

PHA Acquisition Mode

Spectral memory size of 256, 512, 1024, 2048 and 4096 channels

Coarse gain with amplification factors of 1, 2, 4 and 8. Fine gain from 1 to 2 in steps of 1/4096

Upper and Lower Level Discriminator settings given in channels

PHA acquisition presets on:

Live Time

Real Time

Counts on a ROI

or combination of both - time or ROI counts

MCS Acquisition Mode

Spectral memory size of 256, 512, 1024, 2048 and 4096 channels

Dwell time from 0.1 s to “count-forever”

Easy to setup from ROIs or nuclide information.

Digital Settings

Rise Time: from 0.1 to 12 s in steps of 0.2 s

Flat Top: from 0.1 to 8.0 msec in steps of 0.1 usec

Threshold: 1 to 255

Digital Base Line Restorer (BLR)

Pile-Up Rejector (PUR)

High Voltage Power Supply

Miniature HV power supply embedded into the MCA assembly

Voltage: 0 to 1,500 V in 4096 steps

Data Communication

Ethernet, IP address fixed or set via DHCP

Fast transfer rates: 30 μs typical for a 1024-channel energy spectrum

Set of cables and PoE injector​

Environmental

Industrial temperature range: -40 °C to +85 °C

Physical

Size: height 75 mm, diameter 55 mm

Weight: approximately 200 gm

Connectors: Ethernet RJ45

Indicators

Red LED for detector high voltage

Yellow LED for incoming count rate (ICR)

Green LED for power and communication status

Other

The device is supplied with a basic software (free download) to control operation, data acquisition and spectrum visualization.